1. Field of the Invention
The present invention relates generally to an industrial truck having a driving part, a load-receiving device and at least one battery block located in the region of the driving part.
2. Description of the Currently Available Technology
Industrial trucks of the above-described type include, for example, counterweighted fork lift trucks, reach trucks and warehouse trucks, which are typically equipped with a battery block to power the electrical drive of the truck. The battery block and various electrical units are located in the driving part of the industrial truck. Under certain conditions of use of the industrial truck, it is customary to replace a discharged battery block with a charged battery block at regular time intervals. Under other conditions of use, it is customary to leave the battery block in the industrial truck during charging. In this latter case, it is only necessary to change the battery block when there is a fault in the battery block.
Regardless of the conditions of use of the industrial truck, it is desirable to be able to change the battery block with the minimum possible effort. In order to achieve this, known arrangements provide for the battery block to be lifted upwardly out of the industrial truck by means of a crane or, for example, a fork lift truck. Other solutions are known in which the battery block can be withdrawn from the industrial truck in a sideways direction with the aid of a roller conveyor. The side opening of the industrial truck required for this usually reduces its rigidity or involves increased design costs.
Thus, the object of the present invention is to provide an industrial truck of simple construction in which the battery block can be removed from the industrial truck and installed or replaced in the industrial truck in a simple manner.
According to the present invention, there is provided an industrial truck comprising a driving part, a load-receiving device and at least one battery block located in the region of the driving part, wherein the battery block is removable from the driving part in the direction of one main driving direction of the industrial truck, for example, a forward direction or a reverse direction.
The battery block is preferably installed in the driving part in the opposite direction from which it is removed. The main driving directions are defined herein as the forward driving direction and the reverse driving direction of the industrial truck for which no steering angle is required.
Advantageously, at least one battery block may be removable from the driving part in the direction of the load-receiving device. The load-receiving device may incorporate at least one lifting mast on which, for example, a load fork is located to be movable in the vertical direction. The load fork may be raised for removing or installing the battery block in order to avoid a collision with the battery block.
It is expedient for the battery block to be removable from the driving part in the horizontal direction. Thus, movement of the battery block is not effected against its weight either during removal or during installation.
One expedient variant of the invention is obtained when the battery block can be raised at least slightly within the driving part. The raising of the battery block detaches the latter from an anchorage which prevents the battery block slipping during operation of the industrial truck.
It is particularly advantageous when a battery block located within the driving part can be raised by a device disposed outside the driving part, preferably disposed beneath the industrial truck. In practice, the raising device is located beneath the driving part and the battery block is raised. Then the battery block, together with the device, can be moved relative to the industrial truck in the appropriate direction.
It is particularly expedient when a fork lift truck is provided as the device for raising the battery block. The fork of the fork lift truck may be slid under the driving part of the industrial truck, the battery block raised by means of the fork and then withdrawn by means of the fork lift truck. The battery block may be installed in the same manner in the reverse order.
It is expedient when the industrial truck can be moved relative to the raised battery block. One particularly favorable embodiment is obtained when the industrial truck can be moved relative to the battery block by means of its propulsion drive. In this case, the industrial truck can be driven over the stationary battery block with its own propulsion drive.
According to one advantageous variant of the invention, the industrial truck incorporates a lifting framework and the battery block can be moved through a free space located between two pillars of the lifting framework. In practice, a load fork provided on the lifting framework may be raised for this operation.
In this case, it is expedient for the distance between the outsides of the two pillars of the lifting framework to correspond at least approximately to the width of the industrial truck. Thus, the pillars of the lifting mast are spaced as far apart as possible in order to create the necessary space for movement of the battery block.
It is particularly advantageous when a driver""s seat of the industrial truck is disposed above the battery block. However, the industrial truck according to the invention allows any desired configuration of the space above the battery block. When the battery block is designed accordingly, an essentially flat area is created above the battery block which allows an advantageous arrangement of the driver""s seat and hence an ergonomically advantageous design of the driver""s position.
Particular advantages arise when the industrial truck is embodied as a reach truck. In a reach truck the load is usually loaded inside the wheelbase, and the load is only moved outside the wheelbase of the reach truck to place the load in (or remove it from) a shelf. The battery block located under the driver""s position in the operating position acts as a counterweight for a load when the load is located outside the wheelbase of the reach truck. As a result, the wheels of the reach truck on the load side can be located closer to the driving part without jeopardizing the stability of the reach truck. This reduces the overall dimensions of the reach truck in the longitudinal direction, simultaneously improving the maneuverability of the truck. Moreover, the low center of gravity of the battery located beneath the driver""s position, and hence the low center of gravity of the truck, results in an improved sideways stability. Thus, drivability while turning or cornering is improved.
It is expedient when the reach truck incorporates a reach mast. This means that the load can be moved together with the lifting framework in the longitudinal direction of the reach truck. Alternatively or additionally, the reach truck may incorporate a reach fork. In the alternative case, the lifting framework can be connected rigidly to the driving part. This offers design advantages, particularly when the width of the lifting framework corresponds at least approximately to the width of the industrial truck. The reach fork is used to move a load relative to the lifting framework in the longitudinal direction of the industrial truck.